Астронет: Астрономическая картинка дня Ударный кратер Маникуаган http://variable-stars.ru/db/msg/1468324/eng |
Credit & Copyright: NASA,
International Space Station
Expedition 59
Explanation:
Orbiting 400 kilometers above Quebec, Canada, planet Earth, the
International Space Station
Expedition 59 crew captured this snapshot of the broad
St. Lawrence River and curiously circular Lake Manicouagan on April 11.
Right of center, the ring-shaped lake is a
modern
reservoir within the eroded remnant of an ancient 100 kilometer
diameter impact crater.
The ancient crater is very
conspicuous from orbit,
a visible reminder that Earth is vulnerable to
rocks from space.
Over 200 million years old, the Manicouagan crater was
likely caused by the impact of a rocky body about
5 kilometers in diameter.
Currently, there is no known asteroid with a significant probability of
impacting Earth in the next century.
But a fictional scenario to help
practice for an
asteroid impact is
on going
at the 2019 IAA
Planetary Defense Conference.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.